Electrogasdynamic power device for a reciprocating engine

ABSTRACT

An electrogasdynamic converter is attached to the exhaust port of an internal combustion reciprocating engine so that the exhaust gases assist in operation of the converter which produces a pulse of electrical energy for each pulse of exhaust gas. For a multicylinder engine, an EGD converter is provided for each cylinder and the converters are connected in parallel to produce a high voltage DC output or are connected in pairs with opposite polarities to provide a multiphase AC output.

magma {3R stssswzl [72] Inventors Nils L. Muench Bloomfields Hills; Charles B. Lel'iert, Troy, both of, Mich. [211 Appl. No. 841,927 [22] Filed July 15,1969 {45] Patented June 15, 1971 I [73] Assignee General Motors Corporation Detroit, Mich.

[54] ELECTROGASDYNAMIC POWER DEVICE FOR A RECIPROCATING ENGlNE 6 Claims, 3 Drawing Figs.

[52] U.S.Cl 310/10 [51] Int. Cl H02n 3/00 [50] Field of Search 60/29, 31;

310/ll;55/l01,103

[56] References Cited UNITED STATES PATENTS 3,157,479 11/1964 Boles 55/146 3,161,790 12/1964 Percivalet al. 310/11 3,217,696 11/1965 lGekhaefer 123/2 3,452,225 6/1969 Gourdine v 310/11 Primary ExaminerD. X. Sliney Attorneys-Jean L. Carpenter, Paul Fitzpatrick and Warren D. Hill PATENTED JUN 1 51971 AV W/ BY Cdamzs 51 7? A I'TORNHY ELECTROGASDYNAMIC POWER DEVICE FOR A RECIPROCATING ENGINE This invention relates to electrogasdynamic (EGD) converters and particularly to the combination of EGD converters with internal combustion reciprocating engines.

As is well known, EGD converters comprise an ion source i a flowing gas stream and a collector electrode downstream thereof. The ion source is comprised of a small electrode (hereafter called the corona electrode) which is closely spaced from an attractor electrode and a power supply which provides sufficient potential difference between the electrodes to establish a high electric field region around the small electrode to create a corona discharge. A source of high velocity gas is provided to cause gas flow through the interelectrode space whereupon part of the gas is ionized in the corona discharge. Depending upon the polarity of the applied potential, ions of one charge are quickly captured by the corona electrode and the ions of the opposite charge; start to drift toward the attractor electrode. The ions drifting toward the attractor electrode are carried by the gas downstream to a collector electrode. This separation ofcharges creates a very high voltage between the collector electrode and the ion source. By attaching an external load between the collector electrode and ion source (e.g. small electrode) useful flow of electrical current occurs through the load device.

It has been proposed to combine EGD converters with various sources of sustained high velocity gas, for example, turbine engine exhaust. It is desirable, however, to extract electrical energy from internal combustion reciprocating engines which do not have a continuous flow of gas at a sufficiently high velocity to sustain an EGD converter. It has been found, however, that sufficiently high exhaust gas velocities do exist in reciprocating engines in the form of pulses which are adequate to effect intermittent or cyclic operation of EGD converters.

It is therefore an object of this invention to provide in an internal combustion reciprocating engine, efficient means for extracting from the exhaust gases energy which otherwise would be wasted.

It is another object of this invention to provide an EGD converter in an internal combustion reciprocating engine.

It is a further object of this invention to provide in an internal reciprocating combustion engine a combination of EGD converters for producing an alternating current.

This invention is carried out by providing in an exhaust port of an internal combustion reciprocating engine an EGD converter. The invention further contemplates that several converters are so attached to a multicylinder engine and having their outputs interconnected to produce in a common conductor a direct current output.

The invention is also carried out by providing in a multicylinder reciprocating internal combustion engine with an EGD converter in each exhaust port, the converters being connected in pairs with opposite polarities so that multiphase alternating current is produced.

The above and other advantages will be made more apparent from the following specification taken in conjunction with the accompanying drawings wherein like reference numerals refer to like parts and wherein:

FIG. I is a cross-sectional elevational view of an EGD converter fitted in an engine head and manifold according to the invention;

FIG. 2 is a schematic representation of a multicylinder engine fitted with several EGD converters interconnected to produce a multiphase AC output according to the invention; and,

FIG. 3 is a graphical representation of the output produced by the arrangement shown in FIG. 2.

FIG. 1 depicts'a portion of the head of an internal combustion reciprocating engine having an exhaust port 12 with a threaded opening 14. An exhaust manifold 16 surrounds the exhaust port 12 in the conventional manner to collect exhaust gases therefrom. The manifold 16 contains an opening 18 axially aligned with the threaded opening 14 of the port 12. An EGD converter 20 is disposed within the opening 18 and the port 12. The EGD converter 20 comprises a generally cylindrical steel housing 22 having at one end a threaded connection 24 mating with the threaded opening 14 and at the op posite end a flange 26 disposed outside the manifold serving to compress a seal 28 between the flange 26 and the manifold 16 to avert leakage through the manifold opening 18. A plurality of apertures 30 intermediate to the ends of the housing 22 are provided to permit unimpeded communication between the exhaust port 12 and the manifold 16. The housing 22 contains and supports a ceramic insulator 32 which is retained by a snap ring 34 which engages'a suitable groove within the flange 26. The insulator 32 extends through the housing toward the port 12 to a point short of the threaded end of the housing 22. The threaded end of the housing and the adjoining portion of the insulator 32 together define a large central passage 36 which in effect forms a continuation of the exhaust port 12. The insulator 32 is so formed that the passage 36 flares and divides into smaller lateral passages 38 which define openings in the insulator 32 aligned with the apertures 30 in the housing 22 and communicating with the exhaust manifold 16. The other end of the insulator 32 defines a small central bore 40 which supports a tubular collector electrode lead 42 which extends at one end beyond the flange 26 of the housing and at the other end is integral with a collector electrode 44 of streamlined shape which protrudes into the passage 36 and defines a portion of the walls of the passages 38. A corona wire electrode 46 extends from a point near the end of the threaded portion 14 of the housing 22 through the tubular collector electrode lead 42 and through the collector 44 to a point beyond the end of the collector electrode lead 42 where it forms a corona wire lead 47. The corona wire electrode 46 is electrically insulated throughout its length except for its extreme ends with a ceramic insulator 48. A high voltage supply 50 having a voltage (on the order of 2.5 kv.) sufficient to create a corona discharge at the corona wire electrode 46 is connected to the corona wire lead 47. A utilization circuit or load 52 is connected between the collector electrode lead 42 and the housing 22 which is common to the ground of the high voltage supply 50 and an attractor electrode 54. The attractor electrode 54 is comprised of the portion of the threaded end of the housing 22 which is not covered by the ceramic insulator 32. The passages 36 and 38 are preferably large enough that they do not restrict the flow of gases from the port 12 and therefore do not create any significant back pressure in the exhaust system.

In operation, the corona is produced at the tip of the corona wire electrode 46 by reason of the high potential applied thereto and its proximity o the attractor electrode 54 which is, of course, grounded. The corona ionizes the exhaust gas which includes water vapor, other aerosol producing components and aerosols that are excellent carriers of charges to the collector electrode 44. In addition, it is believed that the exhaust gases contain ions even before entering the EGD converter 20 and that these ions may improve the operation of the converter. Although the average velocity of gases in the exhaust port 12 is not sufficient for operating the EGD converter 20, it has been found that the peaks of the gas pulses emitted through the exhaust port do have sufficient velocities to effect intermittent converter operation so that by the mechanism previously described, as each pulse of gas is emitted from the port 12 through the passage 36, a corresponding pulse of electrical current will flow from the collector electrode 44 and through the load 52 to the housing 22. When operating in an open circuit mode, the collector electrode 44 can attain voltages of 50 kv. or larger. The amplitude, shape and duration of each output pulse is dependent upon the nature of the exhaust gas pulse which in turn is a characteristic of the type of engine and its mode of operation. The peak gas velocity in the exhaust port ofa typical automobile gasoline engine operating at 3200 r.p.m. and having an exhaust port area of H3 square inches has been computed to be 530 meters per second at full load l4 p.s.i.a. manifold pressure) and 250 meters per second at part load (7 p.s.i.a. manifold pressure) whereas laboratory tests have indicated a requirement of about 175 meters per second gas velocity for the operation of an EGD converter. The computed gas velocity profile indicates that adequate velocities are available for a period up to 180 of engine crank angle. The actual time duration of each pulse and the pulse frequency is, of course, a function of engine speed. Higher gas velocities are readily obtained by decreasing the area of the passage 36 in the converter 20 to provide better performance of the converter. The practical limit of the resulting restriction of exhaust gas flow is determined by the amount of exhaust back pressure permissible for a given engine application.

In a multicylinder engine having a plurality of EGD converters 20, the collector electrodes 44 may be connected to a common conductor and if the collector electrodes are all operated at the same polarity the common output will be a direct current with a time varying magnitude, depending on the number of converters 20 in the system and the speed ofthe engine.

As shown in FIG. 2, a multicylinder engine 58 having an EGD converter 20 for each cylinder may have the converters 20 interconnected in such a manner as to provide an AC multiphase output. The advantage of AC output lies in the ease of transforming down to lower, and in many cases, more useful voltages. The polarity of the output of each converter is the same as the polarity of its corona wire electrode 46. By providing a high voltage supply 60 with positive and negative output terminals, alternate converters may have their corona wires 46 connected to one terminal of the supply 60 and the remaining converters connected to the opposite terminal. Thus, if the firing order of the six cylinder engine shown in the drawings is l, 5, 3, 6, 2, 4 from left to right, then the converters 20 corresponding to cylinders l, 3 and 5 are connected by the lead 62 to the negative terminal of the voltage supply 60 and those corresponding to cylinders 2, 4 and 6 are connected by the lead 64 to the positive terminal of the supply 60. Since cylinders l and 6, for example, fire at different times and their corona electrodes are charged to opposite polarities, then their collector electrode leads 42 may be commonly connected by a conductor 66 to produce an alternating voltage thereon. Similarly, the converters corresponding to the cylinders 2 and 5 are interconnected by line 68 and those corresponding to cylinders 3 and 4 are interconnected by line 70. Each of the lines 66, 68 and 70 are connected to the utilization circuit or load 52. The output voltages v on these conductors are graphically depicted in FIG. 3. The upper graph of FIG. 3 represents the voltage pulses on the line 66, the positive pulses 1 corresponding to cylinder No. l and the negative pulses 6 corresponding to cylinder No. 6. The middle and lower graphs of FIG. 3 represent the voltages on lines 68 and 70 except that the pulses are displaced by 240 of crank angle. Other forms of interconnection may be readily devised depending upon the number of cylinders or exhaust ports available and the desired electrical output.

It will thus be seen that the invention provides a way of extracting from the exhaust gases of a reciprocating internal combustion engine energy which otherwise would be wasted and converting that energy into electrical energy in the form of DC pulses, fairly constant direct current, single phase AC or multiphase AC, all without detracting significantly from the operation of the engine.

Since obvious modifications and variations will occur to those skilled in the art, the foregoing description and drawing is intended as an illustration of the preferred embodiment of the invention and not as a limitation thereof.

We claim:

1. Means for generating electricity from the waste products of a reciprocating internal combustion engine having an exhaust port for emitting pulses of exhaust gases including means for converting a portion of the energy in the exhaust gases to pulsed electrical energy comprising an electrogasdynamic converter attached directly to the engine at the exhaust port; the converter including exhaust gas passage means for receiving from the exhaust port pulses of exhaust gases having a velocity sufficient to operate an electrogasdynamic converter, means for ionizing at least a portion of the exhaust gases and the particles therein in the passage and for establishing an electrical potential at the upstream end of the passage, and a collector electrode, whereby for each pulse of exhaust gas an electrical potential pulse is produced on the collector electrode.

2. Means for generating electricity from the waste products of a reciprocating internal combustion engine having an exhaust port for emitting pulses of exhaust gases including means for converting a portion of the energy in the exhaust gases to pulsed electrical energy comprising an electrogasdynamic converter attached directly to the engine at the exhaust port; the converter including a corona generating electrode and an attractor electrode, exhaust gas passage means receiving from the exhaust port pulses of exhaust gases having a velocity sufficient to operate an electrogasdynamic converter and extending between and separating the said electrodes, a collector electrode downstream of the first-mentionecl electrodes, a supply means connected between the corona electrode and the attractor electrode for producing a potential difference therebetween capable of establishing a corona discharge a the corona electrode, and utilization circuit means connected between the attractor electrode and the collector electrode; whereby pulses of electrical energy will be produced in the utilization circuit means corresponding to the exhaust gas pulses passing through the passage means.

3. Means for generating electricity from the waste roducts of a reciprocating internal combustion engine having an exhaust port for emitting pulses of exhaust gases including means for converting a portion of the energy in the exhaust gases to pulsed electrical energy comprising an electrogasdynamic converter attached directly to the engine at the exhaust port; the converter including a central axially disposed corona generating electrode and an annular attractor electrode surrounding the corona, annular exhaust gas passage means receiving from the exhaust port pulses of exhaust gases having a velocity sufficient to operate an electrogasdynamic converter and extending between and separating the said electrodes, a collector electrode defining a portion of the passage means downstream of the first-mentioned electrodes, supply means connected between the corona electrode and the attractor electrode for producing a potential difference therebetween capable of establishing a corona discharge at the corona electrode, and utilization circuit means connected between the attractor electrode and the collector electrode; whereby pulses of electrical energy will be produced in the utilization circuit means corresponding to the exhaust gas pulses passing through the passage means.

4. Means for generating electricity from the waste products of a multicylinder reciprocating internal combustion engine having a plurality of exhaust ports for emitting pulses of exhaust gases including means for connecting a portion of the energy in the exhaust gases to pulsed electrical energy comprising a plurality of electrogasdynamic converters each attached directly to the engine at an exhaust port; each converter comprising a passage for receiving from its respective exhaust port pulses of exhaust gases having a velocity sufficient to operate an electrogasdynamic converter, means for ionizing at least a portion of the exhaust gases in the passage and particles entrained therein including a charged corona electrode adjacent the passage, and a collector electrode adjacent the passage downstream of the corona electrode, whereby each converter produces a pulse of electrical energy corresponding to each pulse of exhaust gas passing therethrough; and circuit means connected to the several collector electrodes including a load for interconnecting the several converters.

5. Means for generating electricity as defined in claim 4 wherein some of the converters have their corona electrodes 6. Means for generating electricity as defined in claim 5 wherein the circuit means connects together pairs of collector electrodes of opposite polarity thereby producing an alternating multiphase output. 

1. Means for generating electricity from the waste products of a reciprocating internal combustion engine having an exhaust port for emitting pulses of exhaust gases including means for converting a portion of the energy in the exhaust gases to pulsed electrical energy comprising an electrogasdynamic converter attached directly to the engine at the exhaust port; the converter including exhaust gas passage means for receiving from the exhaust port pulses of exhaust gases having a velocity sufficient to operate an electrogasdynamic converter, means for ionizing at least a portion of the exhaust gases and the particles therein in the passage and for establishing an electrical potential at the upstream end of the passage, and a collector electrode, whereby for each pulse of exhaust gas an electrical potential pulse is produced on the collector electrode.
 2. Means for generating electricity from the waste products of a reciprocating internal combustion engine having an exhaust port for emitting pulses of exhaust gases including means for converting a portion of the energy in the exhaust gases to pulsed electrical energy comprising an electrogasdynamic converter attached directly to the engine at the exhaust port; the converter including a corona generating electrode and an attractor electrode, exhaust gas passage means receiving from the exhaust port pulses of exhaust gases having a velocity sufficient to operate an electrogasdynamic converter and extending between and separating the said electrodes, a collector electrode downstream of the first-mentioned electrodes, a supply means connected between the corona electrode and the attractor electrode for producing a potential difference therebetween capable of establishing a corona discharge a the corona electrode, and utilization circuit means connected between the attractor electrode and the collector electrode; whereby pulses of electrical energy will be produced in the utilization circuit means corresponding to the exhaust gas pulses passing through the passage means.
 3. Means for generating electricity from the waste products of a reciprocating internal combustion engine having an exhaust port for emitting pulses of exhaust gases including means for converting a portion of the energy in the exhaust gases to pulsed electrical energy comprising an electrogasdynamic converter attached directly to the engine at the exhaust port; the converter including a central axially disposed corona generating electrode and an annular attracTor electrode surrounding the corona, annular exhaust gas passage means receiving from the exhaust port pulses of exhaust gases having a velocity sufficient to operate an electrogasdynamic converter and extending between and separating the said electrodes, a collector electrode defining a portion of the passage means downstream of the first-mentioned electrodes, supply means connected between the corona electrode and the attractor electrode for producing a potential difference therebetween capable of establishing a corona discharge at the corona electrode, and utilization circuit means connected between the attractor electrode and the collector electrode; whereby pulses of electrical energy will be produced in the utilization circuit means corresponding to the exhaust gas pulses passing through the passage means.
 4. Means for generating electricity from the waste products of a multicylinder reciprocating internal combustion engine having a plurality of exhaust ports for emitting pulses of exhaust gases including means for connecting a portion of the energy in the exhaust gases to pulsed electrical energy comprising a plurality of electrogasdynamic converters each attached directly to the engine at an exhaust port; each converter comprising a passage for receiving from its respective exhaust port pulses of exhaust gases having a velocity sufficient to operate an electrogasdynamic converter, means for ionizing at least a portion of the exhaust gases in the passage and particles entrained therein including a charged corona electrode adjacent the passage, and a collector electrode adjacent the passage downstream of the corona electrode, whereby each converter produces a pulse of electrical energy corresponding to each pulse of exhaust gas passing therethrough; and circuit means connected to the several collector electrodes including a load for interconnecting the several converters.
 5. Means for generating electricity as defined in claim 4 wherein some of the converters have their corona electrodes charged at a positive polarity and the others of the converters have their corona electrodes charged at a negative polarity thereby producing output potentials at their collector electrode of the same polarity, and circuit means interconnecting the converters to produce an alternating current output.
 6. Means for generating electricity as defined in claim 5 wherein the circuit means connects together pairs of collector electrodes of opposite polarity thereby producing an alternating multiphase output. 